Research Trial to Test New Targeted Therapy for Treating Some Difficult Breast Cancers.
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Enrollment is underway at MedStar Washington Hospital Center for this global, multi-center, placebo-controlled phase III randomized study to evaluate the safety and efficacy of the new PIK3CA kinase inhibitor Inavolisib.


MedStar Health Research Institute is currently enrolling patients in a significant new study titled INAVO 122 that could transform treatment for HER2+ metastatic breast cancers in patients with a gene mutation called PIK3CA, which typically do not respond well to existing therapies.

The study, held in cancer centers worldwide, will seek to understand whether the drug Inavolisib is effective and safe when combined with the medication Phesgo® to treat these cancers. In the past, studies have shown that gene mutation could be part of the reason why they are more challenging to treat.

Human epidermal growth factor receptor 2 positive (HER2+) cells have a protein called HER2 on their surface. Cancer cells that make too much HER2 may multiply and spread. About 15-20% of breast cancers are HER2 positive, and between 12% and 39% of these cancers have the PIK3CA mutation. The PIK3CA gene makes an enzyme called PI3K. When that gene is mutated, too much PI3K can become overactive, causing cancer cells to grow. 

We’ve learned that a one-treatment-fits-all strategy doesn’t work for many patients with breast cancer; even patients with the same cancer subtypes can respond differently to the same treatment. Addressing the PIK3CA mutation may help us answer one of the many questions researchers have asked about why some patients respond better than others.

Phase I trials have helped us determine the proper dosage, so this new phase III study is a f a fascinating move toward even more targeted therapies.


Study details and enrollment criteria.

Participants in this research must have metastatic HER2+ breast cancer and PIK3CA mutation and meet a few other criteria, including: 

  • All HER2+ therapies have a mild risk of cardiac toxicity, which may cause changes in heart function. All study participants will have an echocardiogram to ensure their heart functions properly.
  • Inavolisib can cause hyperglycemia or high blood sugar, so participants must not have diabetes and must have a hemoglobin A1C lower than 6.4%.

Enrolled participants will be randomly assigned to one of two study groups after completing standard induction therapy with taxane-based chemotherapy and either IV pertuzumab and trastuzumab or phesgo.

  • Experimental group: Inavolisib and Phesgo
  • Placebo group: Placebo plus Phesgo

Researchers will measure progression-free survival—the time patients can be on this treatment without progression or spread of cancer. Secondary outcomes we’ll consider include:

  • How does the body metabolize Inavolisib?
  • How did patients feel while taking Inavolisib?
  • Did treatment with Inavolisib improve patients’ quality of life?
  • Overall survival

If you or a loved one is interested in enrolling in this study, talk with your oncologist about a referral or contact Associate Director of Oncology Research Hiwot Guebre-Xabiher at

Always improving cancer care.

As cancer researchers, we’re always looking for ways to improve the care we provide our patients. If Inavolisib effectively improves outcomes for patients with HER2+ breast cancers and PIK3CA mutation, it will give us another tool in our toolbelt. Each new approach helps us offer more people hope for a cancer-free future.

We’ve come so far in the last 10 years, developing therapies like pertuzumab, trastuzumab deruxtecan, tucatinib, and more to treat HER2+ cancers. One reason for these advances is the amazing researchers and research coordinators at MedStar Health Research Institute. We’re proud to be the first site internationally to open enrollment of patients in this critical trial and to provide them with this opportunity to receive this cutting-edge, targeted therapy.

Want more information about this study?

Learn more about eligibility criteria and how to enroll.

Call 833-998-0900 or Contact

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